bots may make the trading game interesting for the most part.... the example of what i think may be a bot trading pattern, didn't change the average price, or the overall trend. what i would worry about with a bot, is if somebody comes up with a bot that consistently moves the price up or down on a certain coin, and uses it to gain leverage.... if that were to happen with regular stocks and bonds. it would be illegal....
That's one of the things about bitcoins/crypto's, a lot of normally illegal stuff is fair game here. It's generally unregulated until someone with the power to do anything catches on. The early days was rife with scamming and pyramid schemes and all sorts of things.
It wouldn't surprise me if these bots already existed, but at least with bitcoins, it's a lot harder to have the capital reserve to make it work. The other currencies (especially devcoins) would be a bit more vulnerable, although with enough people using markm's shotgun approach even bots will start having a harder time trying to make a profit like that.